This invention relates to locking hinges especially for use in a folding shoulder rest for paintball guns.
Locking hinges presently exist in folding shoulder rests built for real guns. Such shoulder rests are not readily adaptable for use on paintball guns. Paintball gun shoulder rests that exist are only telescopic for arm length. Such a paintball gun shoulder rest presents a problem in that the shoulder rest does not fold, allowing for compact storage or compact use of a paintball gun.
The present invention relates to a locking hinge having two rotatable plates. A first hinge plate contains a locking mechanism, which is a spring and a locking cylinder. The locking cylinder has a tapered end directed toward the second hinge plate. A second hinge plate incorporates a tapered circular cavity or notch, which receives the tapered end of the locking cylinder. There is a misalignment of the axis of the locking mechanism and the axis of the tapered circular cavity or notch thereby providing the rigid locking of the hinge plates at predetermined positions. The first and second hinge plates have a symmetrical axis by which mounting holes are located.
An advantage of the present invention is that the intentional misalignment of the locking mechanism allows for increased part tolerances. The increased of part tolerance allows more economic manufacture of the locking hinge.
A further advantage of the present invention is the symmetrical axis of mounting. This allows the reverse swing of the locking hinge. The location of the shoulder rest, and any extra components attached to the auxiliary mounting holes, are not changed.
A next advantage of the present invention is that looseness due to wear of the hinge mating surfaces throughout the hinge life may be significantly reduced by adjusting a connecting bolt that secures the two hinge plates together through the hinge axis.
Another advantage of the present invention is that the combined misalignment and the tapered edges of the locking mechanism provide continues rigid locking and no maintenance during the life of the locking hinge.
A yet another advantage of the present invention is that all locking hinge components may be manufactured using only one type of machine.
A further advantage of the present invention is that it may be used in a variety of manufacturing disciplines including, but not limited to, manufacturing, advertising, military, navy, recreational, marine, automotive, medical, and aerospace. Such disciplines may require locking doors, poles, hatches, and orthopedic devices.